Ladies and gentlemen. Is my comment -- -- -- the president of the United States of America Barack Obama. Mayor Bloomberg. Governor Cuomo. Honored guests. Families of the fallen. In those awful moments. After the south tower was hit. Some of the injured huddled. In the wreckage of the 78 floor. The fires were spreading. The air was filled with smoke. We'll start. I could barely see. It seemed. As if there was no way out. And then there came -- Boortz. Clear him. Call. Saying he had found the stairs. A young man. In his twenties. Strong. Emerged from the smoke and over his nose his mouth he wore red handkerchief. He called for fire extinguishers to fight back the flights. He attended. To the wounded. He -- those survivors. Down the stairs to safety. And carried a woman on his shoulders. Down seventeen flights. Many went back. Back up all those flights -- back down again. Bringing more wounded to safety. Until that moment. When the tower fell. They didn't know his name. They didn't know where it came from. But -- -- -- their lives have been saved. The man in the red -- that. Again Mayor Bloomberg. Distinguished guests -- -- Baggio. It was Christie and Cuomo. And families. And survivors of that day. It's all those who responded with such courage. On behalf of Michelle and myself than the American people. It is honor trust. Joined. In your memories. -- call an -- to reflect. But above all to reaffirm the true spirit. Of 9/11. Compassion. Sacrifice. -- -- -- -- Forever in the heart of our nation. Michelle and I deserve -- -- -- to join -- Others on. A visit it was some of the survivors. And families. Men and women who inspire us all. And we have a chance to visit some of the exhibits. And I think all. Who come here -- find. It to be a profound. And moving experience. I want express our deep gratitude to everybody. Who was involved in this great undertake. For bringing us to this day. For giving us this sacred place. -- and a -- Here that this memorial. This museum. We come together. We stand in the footprints of two mighty towers. Graced by the rush. Of internal waters. We look into the faces -- nearly 3000. Innocent souls of men and women and children of every race every creed. From every corner of the world. We can touch their names. And hear their voices. Glimpse. The small items that speak to the beauty of their lives. A wedding ring. -- -- -- The shining badge. Here and we tell their story. So that generations yet unborn will never. Forget. The co workers who led others to safety. The passengers who stormed the cockpit. -- men and women in uniform who rushed into an inferno. The first responders who charged up those stairs. A generation of service members are 9/11 generation. -- served with honor and more than a decade of war. A nation that stands tall. And united. And unafraid. Because no act of terror to match the strength. The character from our country. But the great wall and bedrock that embraces today. Nothing. Can ever break. Us. Nothing. Can change who we are. As Americans. On that September morning. Allison and brother. -- -- -- -- Months later. She was reading the newspaper. An article about those final minutes. In the towers. Survivors were -- how a young man wearing a red handkerchief. That led them to safety. And in that moment. -- -- Ever since he was aboard her son had always carry. A red handkerchief. The -- wells was the man. In the red Bandana. Wells. Was just 24 years old. -- -- The broad smile and a bright future. He worked in the south tower. More -- fourth floor. Get a big laugh. The joy of life. Dreams saying the world. You worked in finance but it also been a volunteer firefighters. And after the planes hit he put on that bandanna and spent his final moments. Saving others. Three years ago this month. After our seals made sure that justice was done. I came to ground zero. Among the families. -- that day was -- problem. And she told me about -- And his fearless spirit. She showed me a handkerchief like the 1 he wore that morning. Today as we saw heart -- One of his red handkerchiefs. Is on display. In this museum. -- from this day forward. All those who come here. We'll have a chance to know the sacrifice of a young man who like so many and gave his life. So others might look. Those we lost. Live on in us. -- -- -- -- Who love them still. In the friends. Who remember them always. And -- in a nation. The -- honor them. Now and forever.

This transcript has been automatically generated and may not be 100% accurate.

Inside Look at the 9/11 Museum

ABC's David Muir provides a glimpse of the museum honoring the victims of the September 11th attacks.

9/11 Museum Gets Ready to Open

Inside, artifacts including personal belongings, fire trucks and architecture recount the day the WTC was attacked.

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